"use client";

import { useRef, useEffect } from "react";

interface CinematicTextProps {
  text: string;
  className?: string;
  tag?: "h1" | "h2" | "h3" | "p" | "span";
  delay?: number;
  splitBy?: "chars" | "words" | "lines";
}

export default function CinematicText({
  text,
  className = "",
  tag: Tag = "h2",
  delay = 0,
  splitBy = "chars",
}: CinematicTextProps) {
  const containerRef = useRef<HTMLDivElement>(null);

  useEffect(() => {
    const el = containerRef.current;
    if (!el) return;
    if (window.matchMedia("(prefers-reduced-motion: reduce)").matches) return;

    let cleanup: (() => void) | undefined;

    const setup = async () => {
      const [{ gsap }, { ScrollTrigger }] = await Promise.all([
        import("gsap"),
        import("gsap/ScrollTrigger"),
      ]);

      gsap.registerPlugin(ScrollTrigger);

      const spans = el.querySelectorAll("[data-char]");
      if (spans.length === 0) return;

      gsap.set(spans, {
        opacity: 0,
        y: 60,
        rotateX: -90,
        transformOrigin: "center bottom",
        transformPerspective: 600,
      });

      const tl = gsap.timeline({
        scrollTrigger: {
          trigger: el,
          start: "top 80%",
          toggleActions: "play none none none",
        },
      });

      tl.to(spans, {
        opacity: 1,
        y: 0,
        rotateX: 0,
        duration: 0.8,
        ease: "back.out(1.2)",
        stagger: splitBy === "chars" ? 0.02 : splitBy === "words" ? 0.06 : 0.12,
        delay,
      });

      cleanup = () => {
        tl.scrollTrigger?.kill();
        tl.kill();
      };
    };

    void setup();

    return () => {
      cleanup?.();
    };
  }, [text, delay, splitBy]);

  const renderContent = () => {
    if (splitBy === "chars") {
      return text.split("").map((char, i) => (
        <span
          key={`${char}-${i}`}
          data-char
          className="inline-block will-change-transform"
          style={{ whiteSpace: char === " " ? "pre" : undefined }}
        >
          {char === " " ? "\u00A0" : char}
        </span>
      ));
    }

    if (splitBy === "words") {
      return text.split(" ").map((word, i) => (
        <span key={`${word}-${i}`} className="inline-block overflow-hidden">
          <span data-char className="inline-block will-change-transform">
            {word}
          </span>
          {i < text.split(" ").length - 1 && "\u00A0"}
        </span>
      ));
    }

    // lines
    return text.split("\n").map((line, i) => (
      <span key={`${line}-${i}`} className="block overflow-hidden">
        <span data-char className="block will-change-transform">
          {line}
        </span>
      </span>
    ));
  };

  return (
    <div ref={containerRef} className="overflow-hidden">
      <Tag className={className}>{renderContent()}</Tag>
    </div>
  );
}